Helper to fetch backups by ID (#1635)

## Description

Helper function to fetch backup models by ID. Also renames `Backups` to `BackupsByTag`

## Type of change

- [x] 🌻 Feature
- [ ] 🐛 Bugfix
- [ ] 🗺️ Documentation
- [ ] 🤖 Test
- [ ] 💻 CI/Deployment
- [ ] 🐹 Trivial/Minor

## Issue(s)

* #1505

separated from
* #1609 

## Test Plan

<!-- How will this be tested prior to merging.-->
- [ ] 💪 Manual
- [x] ⚡ Unit test
- [ ] 💚 E2E

src/cli/backup/exchange.go

@@ -373,7 +373,7 @@ func listExchangeCmd(cmd *cobra.Command, args []string) error {
 		return nil
 	}
 
-	bs, err := r.Backups(ctx, store.Service(path.ExchangeService))
+	bs, err := r.BackupsByTag(ctx, store.Service(path.ExchangeService))
 	if err != nil {
 		return Only(ctx, errors.Wrap(err, "Failed to list backups in the repository"))
 	}

src/cli/backup/onedrive.go

@@ -272,7 +272,7 @@ func listOneDriveCmd(cmd *cobra.Command, args []string) error {
 		return nil
 	}
 
-	bs, err := r.Backups(ctx, store.Service(path.OneDriveService))
+	bs, err := r.BackupsByTag(ctx, store.Service(path.OneDriveService))
 	if err != nil {
 		return Only(ctx, errors.Wrap(err, "Failed to list backups in the repository"))
 	}

src/cli/backup/sharepoint.go

@@ -261,7 +261,7 @@ func listSharePointCmd(cmd *cobra.Command, args []string) error {
 		return nil
 	}
 
-	bs, err := r.Backups(ctx, store.Service(path.SharePointService))
+	bs, err := r.BackupsByTag(ctx, store.Service(path.SharePointService))
 	if err != nil {
 		return Only(ctx, errors.Wrap(err, "Failed to list backups in the repository"))
 	}

src/cli/utils/testdata/opts.go

@@ -496,7 +496,14 @@ func (MockBackupGetter) Backup(
 	return nil, errors.New("unexpected call to mock")
 }
 
-func (MockBackupGetter) Backups(context.Context, ...store.FilterOption) ([]*backup.Backup, error) {
+func (MockBackupGetter) Backups(context.Context, []model.StableID) ([]*backup.Backup, error) {
+	return nil, errors.New("unexpected call to mock")
+}
+
+func (MockBackupGetter) BackupsByTag(
+	context.Context,
+	...store.FilterOption,
+) ([]*backup.Backup, error) {
 	return nil, errors.New("unexpected call to mock")
 }
 

src/pkg/repository/repository.go

@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"github.com/google/uuid"
+	"github.com/hashicorp/go-multierror"
 
 	"github.com/alcionai/corso/src/internal/events"
 	"github.com/alcionai/corso/src/internal/kopia"
@@ -28,7 +29,8 @@ var ErrorRepoAlreadyExists = errors.New("a repository was already initialized wi
 // repository.
 type BackupGetter interface {
 	Backup(ctx context.Context, id model.StableID) (*backup.Backup, error)
-	Backups(ctx context.Context, fs ...store.FilterOption) ([]*backup.Backup, error)
+	Backups(ctx context.Context, ids []model.StableID) ([]*backup.Backup, error)
+	BackupsByTag(ctx context.Context, fs ...store.FilterOption) ([]*backup.Backup, error)
 	BackupDetails(
 		ctx context.Context,
 		backupID string,
@@ -238,8 +240,29 @@ func (r repository) Backup(ctx context.Context, id model.StableID) (*backup.Back
 	return sw.GetBackup(ctx, id)
 }
 
+// BackupsByID lists backups by ID. Returns as many backups as possible with
+// errors for the backups it was unable to retrieve.
+func (r repository) Backups(ctx context.Context, ids []model.StableID) ([]*backup.Backup, error) {
+	var (
+		errs *multierror.Error
+		bups []*backup.Backup
+		sw   = store.NewKopiaStore(r.modelStore)
+	)
+
+	for _, id := range ids {
+		b, err := sw.GetBackup(ctx, id)
+		if err != nil {
+			errs = multierror.Append(errs, err)
+		}
+
+		bups = append(bups, b)
+	}
+
+	return bups, errs.ErrorOrNil()
+}
+
 // backups lists backups in a repository
-func (r repository) Backups(ctx context.Context, fs ...store.FilterOption) ([]*backup.Backup, error) {
+func (r repository) BackupsByTag(ctx context.Context, fs ...store.FilterOption) ([]*backup.Backup, error) {
 	sw := store.NewKopiaStore(r.modelStore)
 	return sw.GetBackups(ctx, fs...)
 }

src/pkg/repository/repository_load_test.go

@@ -181,7 +181,7 @@ func runBackupListLoadTest(
 		)
 
 		pprof.Do(ctx, labels, func(ctx context.Context) {
-			bs, err = r.Backups(ctx)
+			bs, err = r.BackupsByTag(ctx)
 		})
 
 		require.NoError(t, err, "retrieving backups")